Moisture Measurement and Control is extremely
important in the production of potato chips. Not only does
it impact the taste, but also the texture and shelf-life.

Oil measurement is required for labeling and is needed to
ensure consistency in the flavor of the chips, and provides
important process information concerning the replacement of
slicing knives.

Both measurements can be made off-line, but on-line measurement
is advantageous as feedback is more immediate. The moisture
measurement can be used in an automatic control loop by interfacing
with SCADA systems.

Chip Manufacturing Process
Potatoes are peeled, sliced and de-starched prior to Frying
and Seasoning. Measurements of oil and moisture are typically
made shortly after the exit of the Fryer and after the Seasoning
Cylinders prior to packaging. Moisture measurement at the
exit of the Fryer can be used in closed loop control of the
Fryer to optimize % moisture. This results in greater product
consistency, longer shelf-life and less waste material.

Gauge Installation
Gauges are typically installed after the Fryer over the Vibrating
Conveyor, and prior to packaging at the exit of the Seasoning
Drum. Post Fryer, the gauge should be positioned a minimum
of 1 meter from the exit, in order to allow a degree of equilibration
to occur, and to minimize noise induced by rapid vaporization
of surface moisture. If possible, the gauge should be mounted
10” above the chips, this allows for most variation
in bed depth.

If using the gauge in a control loop, it is very important
to ensure there is a continuous run of product beneath the
gauge and of sufficient bed depth, to prevent the gauge from
viewing the conveyor belt. An ideal measurement location at
the exit of the seasoning drum, is on the drop from the Drum
onto the Conveyor leading to the Bucket Conveyor.

The Food Grade MCT 300 is designed to meet the strict hygiene
and safety requirements of a food manufacturing plant. It
is electro less nickel coated and houses a Kel F or sapphire
window. The MCT 300 is fitted with a sensor window air purge
diffuser to provide a positive pressure thereby minimizing
deposition of oil on the window.

The elevated temperatures found at the exit of the fryer
require the gauge to be fitted with an air/water cooling panel
and/or a Vortex Air Cooler.

Measurement
Performance
Moisture in potato chips is a very well understood and documented
application. Measurement wavelengths, algorithms, and sensor
optical parameters are pre-set at the PSC factory. Gauges
are Pre-calibrated on actual product to facilitate “start-up”.